Illus was a Byzantine general, who played an important role in the reigns of the Byzantine Emperors Zeno and Basiliscus.
Illus supported the revolt of Basiliscus against Zeno, then switched sides, supporting the return of Zeno. Illus served Zeno well, defeating the usurper Marcian, but came into conflict with the dowager Empress Verina, and supported the revolt of Leontius, but the rebellion failed and Illus was killed.